Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions

There are many different ways to keep fit. One of the most important ways is by exercising. Exercising must be done on a regular basis. The amount of exercise done each time is dependent on the free time that a person has. Exercises can be done from twenty minutes to an hour. Sometimes, daily five- minute exercises are just as effective.

Exercising can take place both indoors and outdoors. Those who exercise indoors often do so in the comfort of air-conditioned gymnasiums. They train on equipment that has been specifically designed to tone the different parts of the body. Sometimes, games can also be played indoors. Badminton courts and even some swimming pools are found indoors.

There are many different types of outdoor exercises. These include tennis, cycling and even rock climbing. Most people enjoy outdoor activities because they like being in the sun or are attracted to its sense of peace and quiet. Yet there are others who like the wind blowing against them. Some of these activities are only suitable for people with a taste for adventure.

Exercising is crucial in a different regime. The type of exercise a person takes up depends on his lifestyle and personality. It is important that a person finds an exercise that is suitable for him.

According to the passage, why do some people spend less time exercising?

• A. 
  Five minutes is effective for them.
• B. 
  They do not have much free time.
• C. 
  Gymnasiums are expensive.
• D. 
  They keep fit not by exercising.